@article {534, title = {Kinesthetic Promotion of Function Graph Recognition at University Level}, journal = {Oral Communication at 13th International Congress of Mathematics Education}, year = {2016}, address = {Hamburg - Germany}, author = {Mohamed El-Demerdash and Pedro Lealdino Filho and Christian Mercat} } @conference {LibKorRebMul-TCTA-2013, title = {Tales of a Companion Teacher Analytics}, booktitle = {Proceedings of the 2nd International Workshop on Teaching Analytics (IWTA-2013)}, year = {2013}, keywords = {refereed}, url = {http://ceur-ws.org/Vol-985/paper4.pdf}, author = {Paul Libbrecht and Ulrich Kortenkamp and Sandra Rebholz and Wolfgang M{\"u}ller}, editor = {Ravi Vatrapu} } @inbook {BesHerKorMulZim-ETWIAF-2012, title = {E-learning Tools with Intelligent Assessment and Feedback}, booktitle = {Intelligent and Adaptive Learning Systems: Technology Enhanced Support for Learners and Teachers}, year = {2012}, publisher = {IGI Global}, organization = {IGI Global}, keywords = {refereed}, author = {Bescherer, Christine and Herding, Daniel and Kortenkamp, Ulrich and M{\"u}ller, Wolfgang and Zimmermann, Marc}, editor = {Graf, Sabine and Lin, Fuhua and Kinshuk and McGreal, Rory} } @inbook {Kor-EAVA-2011, title = {Die etwas andere Vorlesung: AnOrMaL}, booktitle = {Mathematik f{\"u}r alle - Wege zum {\"O}ffnen von Mathematik. Mathematikdidaktische Ans{\"a}tze. Festschrift f{\"u}r Wilfried Herget}, year = {2011}, publisher = {Franzbecker}, organization = {Franzbecker}, address = {Hildesheim}, keywords = {invited}, author = {Kortenkamp, Ulrich}, editor = {Krohn, Thomas and Malitte, Eva and Richter, Gerd and Richter, Karin and Sch{\"o}neburg, Silvia and Sommer, Rolf} } @booklet {TrgKorJahLibMerRecSou-IPSDGROE-2010, title = {I2Geo.net {\textendash} a platform for sharing dynamic geometry resources all over Europe}, year = {2011}, keywords = {poster}, author = {Trgalova, Jana and Kortenkamp, Ulrich and Jahn, Ana Paula and Libbrecht, Paul and Mercat, Christian and Recio, Tomas and Soury-Lavergne, Sophie} } @unpublished {LibKorMer-CCBWLTIGR-2010, title = {Crossing Cultural Boundaries with Long Term Interactive Geometry Resources}, year = {2010}, note = {Unpublished Manuscript}, keywords = {sonstige}, author = {Libbrecht, Paul and Kortenkamp, Ulrich and Mercat, Christian} } @conference {MulKor-LPWR-2010, title = {Learning Programming with {Ruby}}, booktitle = {Proceedings of the IFIP Workshop "New developments in ICT and Informatics education{\textquoteright}{\textquoteright}}, year = {2010}, publisher = {IFIP TC3}, organization = {IFIP TC3}, abstract = {

Introducing students into the fundamentals of programming can still be considered as a real challenge. The choice of the right programming language seems to play a major role. In this paper we present our experiences with the programming language Ruby in introductory programming classes. Ruby is a relatively young programming language, which provides some very interesting aspects and seems like a very good candidate as a beginner{\textquoteright}s programming language, integrating the advantages of other languages with respect to learning programming, while still being professional enough to support open-ended learning. We discuss several aspects of Ruby that distinguish it from other languages and which make it a good choice for a beginner{\textquoteright}s course in programming. In addition, we discuss the approaches applied at two different universities in teaching programming with Ruby. We present in some detail the individual programming exercises and present student results. Finally, we discuss the pros and cons for applying Ruby as a first programming language.

}, keywords = {refereed}, author = {M{\"u}ller, Wolfgang and Kortenkamp, Ulrich} } @conference {AbaBotEscHenKorKreLibMarMer-IFFP-2009, title = {The {I}ntergeo File Format in Progress}, booktitle = {Proceedings of the 22nd OpenMath Meeting}, year = {2009}, abstract = {In this paper we describe the ongoing effort to specify a com- mon file format for Interactive or Dynamic Geometry Systems (DGS). Our approach is based on the OpenMath standard, and uses its flexible extension mechanisms like Content Dictionaries. We discuss the various design decisions, the Content Dictionaries that have been defined, as well as open questions to be resolved.}, keywords = {Intergeo, refereed}, author = {Ab{\'a}nades, Miguel and Botana, Francisco and Escribano, Jes{\'u}s and Hendriks, Maxim and Kortenkamp, Ulrich and Kreis, Yves and Libbrecht, Paul and Marques, Daniel and Mercat, Christian} } @conference {AbaBotEscHenKorKreLibMarMer-IFFP-2009, title = {The {I}ntergeo File Format in Progress}, booktitle = {Proceedings of the 22nd OpenMath Meeting}, year = {2009}, abstract = {

In this paper we describe the ongoing effort to specify a com- mon file format for Interactive or Dynamic Geometry Systems (DGS). Our approach is based on the OpenMath standard, and uses its flexible extension mechanisms like Content Dictionaries. We discuss the various design decisions, the Content Dictionaries that have been defined, as well as open questions to be resolved.

}, keywords = {refereed}, author = {Ab{\'a}nades, Miguel and Botana, Francisco and Escribano, Jes{\'u}s and Hendriks, Maxim and Kortenkamp, Ulrich and Kreis, Yves and Libbrecht, Paul and Marques, Daniel and Mercat, Christian} } @conference {LibKorMer-IWIG-2009, title = {I2Geo: a Web-Library of Interactive Geometry}, booktitle = {Proceedings of the 2nd Workshop Towards a Digital Mathematics Library (DML-2009)}, year = {2009}, publisher = {Masaryk University}, organization = {Masaryk University}, keywords = {refereed}, isbn = {978-80-210-4781-5}, author = {Paul Libbrecht and Ulrich Kortenkamp and Christian Mercat}, editor = {Petr Sojka} } @conference {KorBleDohKreLibMer-IIGEFTERFCIP-2009, title = {Interoperable Interactive Geometry For Europe {\textendash} First Technological and Educational Results and Future Challenges of the Intergeo Project}, booktitle = {Proceedings of the Sixth Congress of the European Society for Research in Mathematics Education. January 28th - February 1st 2009, Lyon (France)}, year = {2009}, month = {January}, publisher = {Proceedings of the Sixth Congress of the European Society for Research in Mathematics Education}, organization = {Proceedings of the Sixth Congress of the European Society for Research in Mathematics Education}, address = {Lyon (France)}, abstract = {In this overview article we describe the manifold achievements and challenges of Intergeo, a project co-funded within the eContentplus programme2 of the European Union.}, keywords = {Intergeo, refereed}, url = {http://www.inrp.fr/publications/edition-electronique/cerme6/wg7-11-kortenkamp.pdf}, author = {Kortenkamp, Ulrich and Blessing, Axel M. and Dohrmann, Christian and Kreis, Yves and Libbrecht, Paul and Mercat, Christian} } @conference {KorBleDohKreLibMer-IIGEFTERFCIP-2009, title = {Interoperable Interactive Geometry For Europe {\textendash} First Technological and Educational Results and Future Challenges of the Intergeo Project}, booktitle = {Proceedings of the Sixth Congress of the European Society for Research in Mathematics Education. January 28th - February 1st 2009, Lyon (France)}, year = {2009}, month = {January}, publisher = {Proceedings of the Sixth Congress of the European Society for Research in Mathematics Education}, organization = {Proceedings of the Sixth Congress of the European Society for Research in Mathematics Education}, address = {Lyon (France)}, abstract = {

In this overview article we describe the manifold achievements and challenges of Intergeo, a project co-funded within the eContentplus programme2 of the European Union.

}, keywords = {refereed}, url = {http://www.inrp.fr/publications/edition-electronique/cerme6/wg7-11-kortenkamp.pdf}, author = {Kortenkamp, Ulrich and Blessing, Axel M. and Dohrmann, Christian and Kreis, Yves and Libbrecht, Paul and Mercat, Christian} } @article {KorModOldPolRab-OMAW-2009, title = {Objektorientierte Modellierung {\textendash} aber wann und wie?}, journal = {LOG-IN}, number = {160/161}, year = {2009}, pages = {22-28}, abstract = {

Objektorientierte Modellierung (OOM) ist ein wichtiges Konzept der Fachinformatik und wird von Seiten der Didaktik der Informatik derzeit f{\"u}r den Unterricht in beiden Sekundarstufen stark empfohlen. So wird in den Bildungsstandards f{\"u}r die Sekundarstufe I gefordert, dass alle(!) Sch{\"u}ler und Sch{\"u}lerinnen der Jahrgangsstufen 8 bis 10 ,"f{\"u}r einfache Sachverhalte objekt-orientierte Modelle [entwickeln] und diese mit Klassendiagrammen dar[stellen]" (AKBSI, 2008, S. 47). Die Gr{\"u}nde f{\"u}r die Behandlung der OOM in der Schule sind einleuchtend; es stellt sich aber die Frage, wie fr{\"u}h und wie intensiv sie eine Rolle spielen sollte. Etliche der hier zusammengetragenen Argumente sind nicht neu (siehe z.B. Hartmann, 2005), sollen aber noch einmal bewusst gemacht werden, um eine Abw{\"a}gung zu erm{\"o}glichen.

}, keywords = {lehrer}, author = {Kortenkamp, Ulrich and Modrow, Eckart and Oldenburg, Reinhard and Poloczek, J{\"u}rgen and Rabel, Magnus} } @article {KorMul-DHU-2008, title = {Wo ist denn hier das {U}ndo?}, journal = {Online Tutoring Journal}, volume = {3}, number = {10}, year = {2008}, month = {7}, abstract = {

Welche Besonderheiten haben Dozierende zu beachten, die Lehrveranstaltungen in Second Life anbieten m{\"o}chten? Die Autoren berichten {\"u}ber erste Erfahrungen mit dieser virtuellen Welt und ihrem Einsatz in der Lehre

}, keywords = {invited}, url = {http://www.online-tutoring-journal.de/ausgabejuli08/kortenkamp1.htm}, author = {Kortenkamp, Ulrich and M{\"u}ller, Wolfgang} } @conference {MulBesKorSpa-ICAMCSP-2006, title = {Intelligent Computer-aided Assessment in the Math Classroom: State-of-the-art and Perspectives}, booktitle = {Proceedings of the IFIP WG 3.1, 3.3, \& 3.5 Joint Conference Imagining the future for ICT and Education, Alesund, Norway}, year = {2006}, publisher = {IFIP}, organization = {IFIP}, address = {Alesund}, keywords = {refereed}, author = {M{\"u}ller, Wolfgang and Bescherer, Christine and Kortenkamp, Ulrich and Spannagel, Christian} } @article {GesKorLutMat-VVADM-2005, title = {Visage {\textendash} Visualization of Algorithms in Discrete Mathematics}, journal = {Zentralblatt f{\"u}r Didaktik der Mathematik}, volume = {37}, number = {5}, year = {2005}, pages = {395-401}, abstract = {

Abstract: Which route should the garbage collectors{\textquoteright} truck take? Just a simple question, but also the starting point of an exciting mathematics class. The only "hardware" you need is a city map, given on a sheet of paper or on the computer screen. Then lively discussions will take place in the classroom on how to find an optimal routing for the truck. The aim of this activity is to develop an algorithm that constructs Eulerian tours in graphs and to learn about graphs and their properties. This teaching sequence, and those stemming from discrete mathematics, in particular combinatorial optimization, are ideal for training problem solving skills and modeling {\textendash} general competencies that, influenced by the German National Standards, are finding their way into curricula. In this article, we investigate how computers can help in providing individual teaching tools for students. Within the Visage project we focus on electronic activities that can enhance explorations with graphs and guide students even if the teacher is not available {\textendash} without taking away freedom and creativity. The software package is embedded into a standard DGS, and it offers many pre-built and teacher-customizable tools in the area of graph algorithms. Until now, there are no complete didactical concepts for teaching graph algorithms, in particular using new media. We see a huge potential in our methods, and the topic is highly requested on part of the teachers, as it introduces a modern and highly relevant part of mathematics into the curriculum.

}, keywords = {refereed}, author = {Geschke, Anne and Kortenkamp, Ulrich and Lutz-Westphal, Brigitte and Materlik, Dirk} } @article {KorMat-GTWCEUJJ-2004, title = {Geometry teaching in wireless classroom environments using {Java} and {J2ME}}, journal = {Science of Computer Programming}, volume = {53}, number = {1}, year = {2004}, month = {10}, pages = {71{\textendash}85}, abstract = {

Interactive geometry software is established as an important tool in geometry and math education. We present our research on possible ways to use such software in wireless classroom environments. In particular, we address user interface issues on portable devices and describe how we maintain a common code base for both desktop and mobile environments, thus increasing the stability of the application. We also report on our empirical data comparing different Java virtual machines that are available for portable devices using a prototype implementation of the Interactive Geometry Software Cinderella for J2ME.

}, keywords = {refereed}, doi = {10.1016/j.scico.2004.02.006}, url = {http://kortenkamps.net/papers/2004/wirelessj2me-final.pdf}, author = {Kortenkamp, Ulrich and Materlik, Dirk} } @conference {KorMat-PIGC-2004, title = {Pen-based input of geometric constructions}, booktitle = {Proceedings of MathUI 2004}, year = {2004}, abstract = {

Pen-based input is the classical approach to drawing. Without computers, using a pen was the natural approach to do drawings, and the simplicity of this "device" always called for similar electronic solutions. Today, a broad range of electronic input devices is available that try to pair the simplicity of input with the power of computing. They come in all sizes: from small touch-screens with stylus in personal digital assistants, via desktop-size input tablets or interactive displays, to electronic whiteboards with rear- or front-projection. These devices all share a direct interaction paradigm. The challenge in using these devices for geometric constructions is to automatically annotate the drawn objects with their relations to the other objects. A basic example is the drawing of a right-angled triangle: How can we automatically recognize the user{\textquoteright}s intention to have a right angle? Can we do that at all? Do we really want to do that? If not {\textendash} what is the easiest pen-compatible way to have the user add this information? We will demonstrate several approaches to these problems, implemented in a development version of Cinderella. Another interesting issue is the presentation of hand-drawn figures: Is it possible to preserve the look of a sketch while still guaranteeing mathematically correct figures? Using the additional information gathered by automatic theorem proving we show some solutions.

}, keywords = {refereed}, url = {http://kortenkamps.net/papers/2004/Scribbling-article.pdf}, author = {Kortenkamp, Ulrich and Materlik, Dirk}, editor = {Libbrecht, Paul} } @conference {KorMat-VLLM-2004, title = {Vernetztes Lehren und Lernen im Mathematikunterricht}, booktitle = {Grundfragen multimedialen Lehrens und Lernens. Tagungsband des 2. Workshops GML2004}, year = {2004}, publisher = {Alcatel SEL}, organization = {Alcatel SEL}, keywords = {refereed}, author = {Kortenkamp, Ulrich and Materlik, Dirk}, editor = {Fellbaum, Klaus and Rebensburg, Klaus and Schwill, Andreas} } @conference {RicKor-DACG-2000, title = {Dynamic aspects in computational geometry}, booktitle = {Proceedings of the EACA 2000}, year = {2000}, pages = {51{\textendash}61}, address = {Barcelona}, abstract = {

Computational Geometry very often focuses on static problems, like computing the convex hull or Voronoi complex of a given set of points. Fundamentally new questions arise when the objects under consideration are no longer static, but may move around with respect to certain constraints. This scenario is not unusual, for instance every mechanism can be considered as a dynamic geometry entity. Here we focus on the new areas of problems that arise from genuinely dynamic effects. Constructions from elementary geometry play a crucial role in this context, since they form first natural instances of non-trivial examples where it is reasonable to study the dynamic behaviour. One of the most fundamental problems arises when one considers one point of an intersection of a line and a circle and allows the line to move around. Since the point of intersection is not unique, a computer program has to decide for every "discrete snapshot" which of the two intersection points is meant. If this decision is not made correctly a "path-jumping" of the point may occur. A careful analysis of the situation shows that for a satisfactory resolution of the problem one has to embed the configuration in an ambient complex projective space. One even has to take monodromy effects and underlying Riemann surfaces into account. We will develop a theory for the study of these phenomena. After this, we will investigate the algorithmic complexity of "making the right decision". It will turn out that even in very weak versions this problem is NP-hard. In some stronger versions it is PSPACE hard or even undecidable.

}, keywords = {refereed}, author = {Richter-Gebert, J{\"u}rgen and Kortenkamp, Ulrich}, editor = {Montes, Antonio} } @inbook {KorRic-C-1999, title = {Das {C}inderella-{P}rojekt}, booktitle = {Erfahrungen mit Java}, year = {1999}, pages = {381{\textendash}401}, publisher = {dpunkt.verlag}, organization = {dpunkt.verlag}, chapter = {17}, address = {Heidelberg}, keywords = {refereed}, url = {http://www.amazon.de/exec/obidos/ASIN/3932588339/theinteractive07}, author = {Kortenkamp, Ulrich H. and Richter-Gebert, J{\"u}rgen}, editor = {Maffeis, Silvano and Toenniessen, Fridtjof and Zeidler, Christian} }